Test your Agent Skills before your agents do.
SKILL.md files can be syntactically valid and still be bad: a vague
description that never routes correctly, an oversized file that eats context,
a curl | sh buried in a code block, a hardcoded /Users/you/... path that
only works on your machine. SkillSeal is a local-first, offline-first CLI
that lints, scores, and routing-tests SKILL.md files — catching what a
manual read-through misses, before an agent does.
| Category | Catches things like |
|---|---|
| Specification | Invalid frontmatter, a name that doesn't match its directory |
| Quality | Vague descriptions, oversized files, dangling file references |
| Security | rm -rf / curl | sh in a code block, secret-file reads |
| Portability | Hardcoded /Users/you/... paths, OS-specific commands |
Full docs: https://pespinel.github.io/skillseal/
uv tool install skillseal
# or: pipx install skillseal
# or: pip install skillsealOne-off, no install:
uvx skillseal check ./skillsskillseal check ./skills # lint: spec, quality, security, portability
skillseal test ./skills # routing tests (skillseal.yaml)
skillseal conflicts ./skills # duplicate names / routing overlap between skills
skillseal diff old/ new/ # score delta between two versions of a skillSee the full command reference,
skillseal.yaml/skillseal.toml config,
and CI integration (GitHub Action,
pre-commit hook) on the docs site.
See AGENTS.md for setup, quality gates, and how to add a rule. Planned work is tracked in Issues.